Why are there so many colorful carp flags all over Japan at this time of the year? Because May 5 is a special day for the boys, and is an official holiday in Japan.
So why the carps?
During the Edo period, people celebrated the healthy growth of boys on the 5th of May, when a shogun had a newborn boy.
The Boys’ Festival is called “Tango no sekku.” (The Girls’ Festival is known as “Momo no sekku” or “Hinamatsuri.”)
In 1948, after World War II, “Tango no sekku” was given another name: “Kodomo no hi,” which means “Children’s Day.”
However, people still use both “Kodomo no hi” and “Tango no sekku.”
At this time of year, it is common for a big family that has a son or sons to decorate their house with a flag and Japanese armor, helmets, or Musha ningyo (Warrior dolls) to wish for their son’s health and success.
The carp symbolizes success in life, as the carp turns into the dragon in Chinese ancient fairy tale. So Japanese people draw colorful carps on the flags and hang them outside the house, wishing the boys will be strong and successful in their life. People call the carp flags "Koinobori".
Let's raise "Koinobori" for your son!
Blue Koinobori at Higashi Matsushima, Miyagi prefecture ( Photo by Norikazu Fukushima)
Koinobori and Sakura together at Kitakami, Iwate prefecture (Photo by Mizuho Miyazaki)
Waving Koinobori at Ohzu, Ehime prefecture
Giant Koinoboris at Hitachiota, Ibaragi prefecture